diff --git a/django/conf/urls/defaults.py b/django/conf/urls/defaults.py
index 49bc176ef3..13a74331d6 100644
--- a/django/conf/urls/defaults.py
+++ b/django/conf/urls/defaults.py
@@ -11,9 +11,10 @@ def patterns(prefix, *args):
     pattern_list = []
     for t in args:
         if isinstance(t, (list, tuple)):
-            pattern_list.append(url(prefix=prefix, *t))
-        else:
-            pattern_list.append(t)
+            t = url(prefix=prefix, *t)
+        elif isinstance(t, RegexURLPattern):
+            t.add_prefix(prefix)
+        pattern_list.append(t)
     return pattern_list
 
 def url(regex, view, kwargs=None, name=None, prefix=''):
diff --git a/django/core/urlresolvers.py b/django/core/urlresolvers.py
index c4cbccabcf..38b3263da1 100644
--- a/django/core/urlresolvers.py
+++ b/django/core/urlresolvers.py
@@ -102,6 +102,14 @@ class RegexURLPattern(object):
         self.default_args = default_args or {}
         self.name = name
 
+    def add_prefix(self, prefix):
+        """
+        Adds the prefix string to a string-based callback.
+        """
+        if not prefix or not hasattr(self, '_callback_str'):
+            return
+        self._callback_str = prefix + '.' + self._callback_str
+
     def resolve(self, path):
         match = self.regex.search(path)
         if match: